Shadow Claw Gengar reroll?
I have a IV 66.7% (4/11/15 ADS) SC Gengar, at level 30. It is from 2016, for what it's worth (I don't know how the lucky chance works).
Would you trade this in hopes of a reroll?
Assume I do it with an best friend, the odds are slightly in my favour (50/50 of getting better/worse as the IV is 66.7%), but since there is a lucky chance, I will on average get better than 66.7% IV.
I am also going to get a better attack IV for sure (5 minimum).
On the other hand, attack on gengar, especially shadow claw, does not seem to be a decisive factor in strength. The relatively high defense/stamina seems like a much bigger strength for my gengar.
Note: I have 3 other shadow claw gengar, all are IV 80 or above, and I maxed two.
Answers
I'm not a data miner but I assume it's a lot easier to discover extra models being added than it is to crack a specific algorithm.
As for the Gen 4 Pokemon, we've had the base stat conversion formula for a long time now. Taking base stats from the main series we can project Go stats for any unreleased generation, including Gen 7. When Gen 8 drops I'm sure people will begin calculating Go stats to see what to look out for when it gets added 5+ years later. Speaking of, how long did it take to crack the BSCF anyway?
Raids I always assumed were discovered via reports of what's been seen in game as opposed to data mining, but I could be wrong.
It takes a lot more time and data to unlock Trading secrets than you may think, especially if Niantic changes the frequency of Luckies. At one point in the Trade Event I was getting Luckies every 5th or 6th trade. Thereafter rate went down notably for me. I suspect that a group like Silph Road and other data crunchers will post a study soon.